package com.zy511.cowmall.product.service.impl;

import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.zy511.common.utils.PageUtils;
import com.zy511.common.utils.Query;

import com.zy511.cowmall.product.dao.CategoryDao;
import com.zy511.cowmall.product.entity.CategoryEntity;
import com.zy511.cowmall.product.service.CategoryService;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1.查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);
        //2.组装成父子的树形结构

        //2.1找到所有的一级分类
        List<CategoryEntity> level1Menus = entities.stream().filter(categoryEntity ->
             categoryEntity.getParentCid() == 0
        ).map((menu)->{
            menu.setChildren(getChildren(menu, entities));
            return menu;
        }).sorted((menu1, menu2) -> {
            return (menu1.getSort()==null ? 0 : menu1.getSort()) - (menu2.getSort()==null ? 0 : menu2.getSort());
        }).collect(Collectors.toList());


        return level1Menus;
    }

    @Override
    public void removeMenuByIds(List<Long> list) {
        //TODO 1.检查当前被删除的分类是否被引用

        //逻辑删除
        baseMapper.deleteBatchIds(list);
    }

    @Override
    public Long[] findCatelogPath(Long catelogId) {
        List<Long> paths = new ArrayList<>();

        List<Long> parentPaths = findParentPath(catelogId,paths);

        Collections.reverse(parentPaths);

        return parentPaths.toArray(new Long[parentPaths.size()]);
    }
    private List<Long> findParentPath(Long catelogId, List<Long> paths){
        paths.add(catelogId);
        CategoryEntity byId = this.getById(catelogId);
        if(byId.getParentCid()!=0){
            findParentPath(byId.getParentCid(),paths);
        }
        return paths;
    }

    //递归查找所有菜单的子菜单
    public List<CategoryEntity> getChildren(CategoryEntity root, List<CategoryEntity> all){

        List<CategoryEntity> children = all.stream().filter(categoryEntity ->
            categoryEntity.getParentCid() == root.getCatId()
        ).map((menu)->{
            //1.找到子菜单
            menu.setChildren(getChildren(menu, all));
            return menu;
        }).sorted((menu1, menu2) -> {
            //2.菜单排序
            return (menu1.getSort()==null ? 0 : menu1.getSort()) - (menu2.getSort()==null ? 0 : menu2.getSort());
        }).collect(Collectors.toList());

        return children;
    }
}
